Perhaps Elon Musk and Starlink could be held liable for the hundreds of thousands of tax dollars needed to replace data ruined at professional observatories caused by their blanketing the skies with satellites...

Comets are icy messengers from deep in space. The short period comets (<100yrs) mostly originate from the Kuiper Belt beyond Neptune. The long period comets are thought to originate from the Oort Cloud, tens of thousands of au from the Sun. (46P/Wirtanen shown)

@pzmyers Is it getting emails from students the night before a major observational project is due (one that was announced months before) asking which is the fastest to do?

N63A: Supernova Remnant in Visible and X-ray

Image Credit: NASA, ESA, Hubble, Chandra; Processing & License: Judy Schmidt #APoD

M101 is a spiral galaxy located in the constellation of Ursa Major. It is about 20 million light years away.

The difference focal length and aperture make. Same cluster (M37). On the left, 12.7cm aperture, 1500mm focal length. On the right 20.5cm aperture, 800mm focal length.

Looking Sideways from the Parker Solar Probe

Video Credit: NASA, JHUAPL, Naval Research Lab, Parker Solar Probe #APoD

M20, the Trifid nebula is located in the constellation of Sagittarius. A star formation region it also shows the three basic types of nebula, emission (red), reflection (blue), and dark (the black bands over the red part).

Globular clusters (like M2, shown here) are balls of 10s to 100s of thousands of stars that orbit our Galaxy as well as other galaxies. Generally they are made up of older lower metal stars. We don't have a good idea on how they form or where they come from.

At the end of their lives stars greater than 8 times the mass of the Sun explode in a supernova. Pictured is the Crab Nebula, a remnant of a supernova witnessed in 1054. In the centre of the nebula is a rapidly spinning neutron star called a pulsar, the remnant of the star.

Jupiter and its 4 large moons. These moons are easily observed through a pair of binoculars and if you watch them night after night you can see them orbit Jupiter.

This is a composite image since to see the moons Jupiter has to be over exposed.

Mercury Crosses a Quiet Sun

Video Credit: NASA, SDO, NASA's Science Visualization Studio; Music: Gustav Sting (Kevin MacLeod) via YouTube #APoD

@rook @APoD looking at it and given the likely exposure it’s a meteor.

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